Dead Speedo

Hit a pothole and the speedo dropped to zero.
I got home and took the wheel off this afternoon and checked the wheel speed sensor and it looked ok, was still attached and the wires were attached to the sensor, unplugged it and its dirt free.

Whats next to try? Everything else on the stack is working.

Its not majorly urgent as the car is in for a service in just over a week but its a pain working out your speed, especially when I just had a police car following me :stuck_out_tongue:

The ECU wheels speed is on the drivers side and the stack one is one the PX side, did you check the right one

Otherwise it could have come loose, was it close enough to the notched hub?


If it was deffo related to the pot-hole then it’s nearly certain that it’ll be the pick-up at the rear wheel… like RL says, make sure you check the correct one.

It was deffo the pothole as I saw it go, it was the PX side I checked and the hub did look close enough.

I don’t know what failure modes these could have but how did you convince yourself it is okay??..

if its in for a service you could get the dealer to check it?

let us know what happens


If the pothole caused it there can only be three possabilities:

  • The connections were not good and the shock caused them to come apart - If you had the plug apart and re-fitted then that should be ok but I had a similar problem with the ECU wheel speed sensor and that needed some wd40 in it and a good clean up before I got it working correct again - the plugs are tie wrapped quite tight to the wishbones … I would really check that out again …

  • The shock moved the sensor away just enough to stop it picking up the teeth - easy to check as it difficult to move the sensor in the plate anyhow and I doubt that - but if you take the sensor off and run some metal past it and see if you get a trigger ( ign on etc )

  • The sensor got damaged somehow … is the face still ok ? - not looking like it got scraped or anything ?

i had a similar problem with my old Elise. When i took it to Lotus they said it was a broken wire.

Not had chance all weekend to take another look with your suggestions, will try and get a peek 2moro, if not I’ll probably wait until its service on Monday. Thinking about it, the wire was clamped pretty tight to the car and may have broken there, will take a better look.

Thanks for your help, will let you know.

Turns out it was a broken wire in the centre console, thanks for your help.